UFH manifold vibrating

NickTellis

The manifold to our newly installed UFH system is vibrating quite noisily whenever the pump kicks in. Does anyone have any solutions to this? Could trapped air in the system causing this? Is a certain amount of vibration to be expected and, if so, could some sort of rubber baffle be used to stop it?

heinbloed

In case air is in the group or in the circuits the automatic air valve would eliminate this. These air valves ("bleeding valves") are found on each group, on the flow as well as on the return.

Make sure they are both open at all times.

Is this noise only observed when the pump kicks in or at all time, for example when the pump is running but the boiler not firing?

...could some sort of rubber baffle be used to stop it...

There should be little rubber footings on the brass groups, between the group and the wall fixings, the holders of the group.
But these are designed to avoid contraction and expansion noises when cooling or warming up.
These rubber footings are not designed to do away with vibrations.

NickTellis

heinbloed wrote: »

In case air is in the group or in the circuits the automatic air valve would eliminate this. These air valves ("bleeding valves") are found on each group, on the flow as well as on the return.

Make sure they are both open at all times.

Is this noise only observed when the pump kicks in or at all time, for example when the pump is running but the boiler not firing?

It's only noisey when the pump is in operation.

heinbloed

It's only noisey when the pump is in operation.

Only when the pump kicks in for a few seconds or at all the time when the pump is running?

NickTellis

heinbloed wrote: »

Only when the pump kicks in for a few seconds or at all the time when the pump is running?

It's only for about 10 - 20 seconds when the pumps kicks in... then it settles down.

heinbloed

Two things come into my mind:

1.)There is air in the pump and - after a while- pumped out. This will cause vibrations which can be distributed through the entire CH system.

2.)The valves at the group need a minimum pressure to open and are vibrating whilest the pressure is building up. This is a very rare phenomena, usually the wrong outlay of components the cause of it.

Is the CH system designed to be pressurised or is it a vented system, an open system? What does the barometer show?

Was this problem always present with the heating system or did it appear only recently ?

And again: Are the air valves at the groups open?

NickTellis

Plumber came and flushed the air out of the system - UFH now running smoothly and quietly. Thanks for the help and advice.